Ventilating apparatus and method



5 M. w. PATRICK 3,198,500

VENTILATING APPARATUS AND METHOD Filed May 21, 1962 2 Sheets-Sheet 1 I INSIDE AIR OUTSIDE AIR INVENTOR Malcolm W. Patrick ATTORNEYS Aug. 3, 1965 M. w. PATRICK VENTILATING APPARATUS AND METHOD 2 Sheets-Sheet 2 Filed May 21, 1962 INVENTOR Malcolm W. Patrick ATTORNEYJ United States Patent 7 ice 3,198,590 VENTILATING A?PARATUS AND METHGD Malcolm W. Patrick, Bradford, Ghio, assignor to I-lupp Corporation, Cleveland, (lists, a corporation of Virginia Filed May 21, 1%2, Ser. No. 196,313 14 Claims. (Cl. 263-19) This invention relates to ventilating apparatus and, more specifially, to forced draft ventilating apparatus for bringing outdoor air into a building, tempering the outdoor air with air recirculated from the building interior, and delivering the air in a curtain along the inside of the building wall or ceiling. The ventilating apparatus provided by the present invention is especially useful in ventilating industrial and other larger buildings heated with unvented gas burning radiant heaters but is by no means limited to this application.

In ventilating buildings heated by unvented gas burning heaters, two requirements must be met. First, the combustion products generated by the heaters must be diluted with fresh air and removed from the building to prevent unwholesome concentrations of noxious gases, primarily carbon dioxide, from accumulating. In addition, suflicient fresh air must be circulated to prevent coudensation of moisture on the inside of the building roof and side walls when outdoor temperatures are low. If condensate is allowed to form it will drip onto machinery, equipment and goods stored in the building, causing rust and other damage. To prevent condensation, the prodnets of combustion are diluted with circulating fresh air to such an extent that the dew-point of the resultant mixture will not be reached even when it is chilled by contact with a cold roof or other wall structure. Thus, both the prevention of noxious gas accumulations and condensation of moisture on the building wall and roof interiors surfaces is dependent upon the circulation within the building of large amounts of air.

If the motive power for the air movement (either induced or natural draft) is located at the vents for the 3,198,599 Patented Aug. 3, 1965 hour, it is necessary to supply at least 227,000 cubic feet per hour or 3791 cubic feet per minute of outside air to the building.

It has been found by the inventor herein that the most satisfactory ventilation is achieved when the building is maintained under a slight overpressure by forcing the air into the building, provided this is done without creating objectionable drafts by blasts of entering cold air. Forced draft circulation promotes more effective mixing of the ventilating air and the combustion products generated by the building heaters. In addition, since the building is maintained at an overpressure, air will not enter through cracks or other openings and the tendency toward draft conditions will be greatly reduced.

It is, therefore, an object of the present invention to provide ventilating apparatus for supplying fresh air to and removing products of combustion from a building heated by unvented combustion heaters which will maintain the building at a slight overpressure, which will circulate sufiicient air to prevent the condensation of moisture on the interior surfaces of the building and insure a comfortable and healthful atmosphere in'the building, which will maintain the concentration ofcarbon dioxide at an acceptable limit, and which will operate without producing objectionable drafts in the building.

A further reduction of objectionable drafts will result if the ventilating air is discharged as a curtain along the buildings interior Wall surfaces instead of generally toward the central portions of the building as in previous ventilating systems. If the outdoor air is cold, an even further reduction of objectionable drafts can be produced by tempering the outdoor air with warmer air recombustion products, as has heretofore been the practice,

the building interior will be at subatmospheric pressure. Air will then enter though openings, through cracks in the walls, along the floors, and around windows and doors, producing drafty conditions objectionable to the building occupants.

Moreover, unless very large vents are employed, air circulation will be inadequate to stop condensation, particularly when the building is closed, as at night or on weekends. Again, one side of the building may be dry and the other side dripping since, on windy days, air will enter the building only from the windward side.

In the winter months, these problems are compounded. As the outdoor temperature drops, more fuel will be burned, producing more moisture, and the roof will become colder. Consequently, there will be a greater tendency for condensate to form and a demand for an increased circulation of air to prevent its formation. Because, under such circumstances, the air will be colder and will be supplied in greater volume, there will be a greater tendency to create objectionable drafts in the build mg.

Even when the roof is insulated Well enough that condensation is not a problem, enough air must be circulated through the building to dilute the products of combustion so that the concentration of carbon dioxide will not exceed 5000 parts per million parts of air (which is the maximum permitted by health standards). This degree of dilution requires at least 227 cubic feet of air per 1009 B.t.u. of natural gas burned in the building. Thus, if a building has heaters which burn one million B.t.u. per

circulated through the ventilating apparatus from the interior of the building. Alternatively, the warm room air may be discharged as a separate curtain between the curtain of outdoor air and the interior of the room with much the same results.

A further object of the present invention, therefore, is to provide ventilating apparatus which will draw in outdoor air and deliver it as a curtain along a building interior. wall surface and which will draw in interior air and mix it with the outdoor air to raise the temperature of the latter or cause it to move as a curtain between the curtain of outdoor air and the air in the room.

It is a further specific object of the present invention to provide ventilating apparatus for an enclosed space which includes a motor-driven, double-ended, centrifugal blower wheel, one end of which draws fresh outdoor air though an opening in a wall bounding the space and the other end of which draws air from within the space and which delivers the outdoor and indoor air as a curtain adjacent the wall.

To this end, one or more air inlet openings are provided in the building side walls and each opening is communicated with one inlet of a double-ended centrifuugal blower wheel mounted directly on the shaft of a driving motor. The opposite inlet is maintained in open communication with the interior of the building. The blower wheel is surrounded by a housing having a circumferential outlet slot which receives the discharge from both ends of the wheel.

As the blower wheel is rotated it will draw in outdoor air through the inlet communicating with the exterior of the building through the air inlet opening and deliver it through the outlet slot in the blower housing as a radially 3 the preferred embodiment, the position of the blower wheel may be shifted relative to the outlet slot to vary the ratio of indoor to outdoor air.

While the ventilator provided by this invention is particularly suited to supplying fresh outdoor air to industrial buildings for the purposes described above, it has appli cation wherever it is desired to circulate fresh outdoor air in an enclosure without creating uncomfortable conditions. For example, in rooms occupied by many people, good ventilation may be necessary to remove smoke and odor and to lower the humidity, even though heating nor cooling is not required. Ventilation may also be needed under similar conditions while heating or cooling is supplied. To fulfill these requirements, the ventilating apparatus provided by the present invention can be installed in the ceiling of the room to circulate fresh air tempered by recirculated room air in a curtain across the ceiling of the room and along its walls and force stale air out of the room through outlet vents in the walls. :Another object of the present invention therefore resides in the provision of novel ventilating apparatus for removing air laden with smoke, odors, or excess moisture from an enclosure and replacing it with fresh outdoor air without the creation of drafts in the enclosure.

Ventilating apparatus of the same general character as that provided by the, present invention has been made in the past, often as part of an air-conditioning unit or system. However, the prior art devices have, for the most part, involved proportioning or mixing dampers and/or complicated housings and ducts, have required excessive floor space, and have not been suitable for supplying the large volumes of fresh air required by large industrial buildings heated with unvented heaters.

Further objects of the present invention, therefore, are to provide ventilating apparatus in accordance with the foregoing objects which is simple, reliable, free from the need for service, easy to install, economical to operate, which requires no floor space, and which has an adequate capacity for use in industrial and other large buildings.

Another object of the present invention is to provide ventilating apparatus which can be manufactured at a lower cost than prior art ventilating apparatus of similar capacity.

A still further object of the present invention is to provide novel methods for ventilating and for heating and ventilating structures.

Additional objects and advantages of the invention will become apparent from the appended claims and from the following detailed description of typical embodiments, taken in conjunction with the accompanying drawing, in which:

FIGURE 1 is a vertical section through a building heated by unvented heaters and ventilated by the ventilating apparatus of the present invention;

FIGURE 1A is a fragment of FIGURE 1, to a larger scale, showing the air flow pattern produced by the ventilatin g apparatus of FIGURE 1; :FIGURE 2 is a transverse section of a preferred form of ventilating blower together with a portion of the wall to which it is fixed and is taken substantially along line Z2 of FIGURE 3;

FIGURE 3 is a view of the blower shown in FIGURE 2, looking substantially in the direction of arrows 33 in FIGURE 2; i FIGURE 4 is .a view similar to FIGURE 2 of a modified blower, taken substantially along line 44 of FIG- URE 5;

FIGURE 5 is a view of the blower of FIGURE. 4, looking substantially in the direction of arrows 5-5 in FIGURE 4;

FIGURE 6 is a diagrammatic illustration of .a control system for the heaters and ventilating apparatus of FIG- URE l: and

FIGURE 7 is a section through a building showing an alternate installation of the ventilating apparatus provided by the present invention.

Referring now to FIGURE 1 of the drawing, the novel ventilating blowers 8 of the present invention are installed in a building 10 which has side walis 12, a roof 14 and a ridge ventilator 15. The building is heated by a plurality of overhead radiant heaters 16 which burn a gaseous fuel supplied to them through pipes 18.

Radiant heaters 16 are preferably of the type disclosed in United States Patent No. 2,775,294 issued to Gunther Schwank, December 25, 1956, although any suitable radiant heaters may be employed. :These heaters per se forrn no part of the present invention and a detailed description of them is not therefore deemed necessary. Heaters 16 are mounted to project the infrared rays which they generate in a generally downward direction as indicated by wavy arrows 20. These rays warm the floor, occupants and objects in their path. Heaters of the type described above are especially suited for and are often used to heat warehouses, mills and other high-bay buildings.

The products of combustion generated by heaters 16, which consist primarily of carbon dioxide and water vapor, are warm and therefore tend to rise toward roof A- and pass out of the building through ventilators 15. The general path of these combustion products is indicated by arrows 22.

As the moisture-laden combustion products rise, they will mix with rising air warmed by heaters 16 which may also have a significant moisture content. Eventually, the moisture-laden mixture of .air and combustion products will contact the cold interior surface of roof 14. If the outside temperature is sufliciently low, the mixture will be cooled to a temperature below its dewpoint and water will condense on the cold roof and drip onto whatever is located below.

If the dewpoint of a moist body of gas is lower than the temperature of a surface contacted by it, the water vapor in the gas will not condense on the contacted surface. The dewpoint of a body of gas is dependent upon the concentration of water vapor in the gas and may be lowered by reducing the moisture content of the gas. In the present invention this is done by diluting the moistureladen mixture of combustion products and warmed building air with relatively dry air drawn in from the exterior of the building. To draw in the requisite amounts of fresh outdoor air from the exterior of building 10, blowers 8, installed in walls 12 at an elevation below the plane of heaters 16, are employed. The preferred form of blowers 8 is shown in FIGURES 2 and 3.

Referring next to these figures, each blower 8 includes a flat, annular mounting plate 26 attached to wall 12 by screws 27. Fixed to one side of mounting plate 26 as by welding is a cylindrical sleeve 28 which extends through an appropriately-sized hole 29 in wall 12. Sleeve 28 forms an inlet duct through which outdoor air is drawn when blower 8 is operating. In the illustrated embodiment, sleeve or duct 28 is about eleven inches in diameter and six inches long.

Fixed to mounting plate 26 on the side opposite sleeve 23 as by welding are four angle irons 30 spaced at equal intervals around the mounting plate periphery. Angle irons 30 support a dish-shaped air deflecting ring 32 which may be attached to the angle irons in any desired manner. In the preferred embodiment shown in FIGURES 2 and 3, ring 32 has a cylindrical peripheral portion 34 and a fiat annular wall portion 36 separated by an arcuately sectioned, annular intermediate portion 38. The flat wall portion 36 has a central opening 40 of substantially the same diameter as the interior of inlet sleeve 28. Angle irons 30' support air deflecting ring 32 in spaced relationship to mounting plate 26, providing an outlet passage 42 through which air leaves the blower when it is in operation. In the illustrated embodiment outlet passage 42 is on the order of 2 inches wide.

Attached to the convex side of ring 32 in any suitable manner is a blower inlet cylinder 44 which has a diameter slightly greater than opening 40 and, in the preferred blower embodiment, a length of about 6 inches. This cylinder serves to guide air from the interiorof building into blower 8 when the latter is operating.

Disposed within cylinder 44 is a circular band 46 which is fixed to the cylinder by screws 48 extending through slots 50 in the cylinder into drilled and tapped apertures (not shown) in band 46. Slots 50 are longitudinally elongated, permitting longitudinal movement of the band 46 and certain blower components which it supports in a manner pointed out in the following paragraphs.

Attached to band 46 by bolts or screws 51 are three support arms 52 to which is welded a motor supporting cradle 54. Located substantially in the central opening 40 in mounting plate 26 is an electric blower motor 56 secured in motor supporting cradle 54 by suitable fasteners such as screws 57 which extend through wall 58 of the cradle into drilled and tapped apertures (not shown) in the motor housing and supported by the cooperation of motor housing end bell 59 which extends through an aperture 60 in cradle 54. Motor 56 may be connected by appropriate leads (not shown) to any suitable source of power through any desired control or switching arrangement.

Motor 56 has an output shaft 61 to which is fixed the hub 62 of a centrifugal, double-ended blower wheel 63. In the illustrated embodiment blower wheel 63 is 10- inches in diameter and 8 inches long. The blower wheel has conventional longitudinally extending blades 64 arranged in a cylindrical configuration and fixed at their opposite ends to annular rings 65. Blower wheel 63 is divided, intermediate its ends, by a transverse center partition 66 attached to hub 62 and to blades 64. One end 67 of the blower wheel communicates with the exterior of building 10 through inletsleeve 28 and the other end 68 communicates with the interior of the building through inlet cylinder 44. Blower wheel 63 is sized to permit the free passage of air around blower motor 56.

Blower motor 56 rotates blower wheel 63 which draws outdoor air into its open end 67 through inlet sleeve 28 and drives it radially outward through outlet opening 42 along the interior surface of wall 12 of building 10. Indoor air is drawn into the opposite blower end 68 through inlet cylinder 44 and is driven radially outward against the concave wall portion 38 of air deflecting ring 32, which deflects it into and forces it to mix with the outdoor air as the latter passes through outlet opening 42. The directions of air flow are indicated by the arrows associated with blowers 8 in FIGURES 1 and 2.

As illustrated in FIGURE 2, blower wheel partition 66 is positioned between the plane of mounting plate 26 and the plane of flat wall portion 36 of dished air deflecting ring 32. The effective discharge area of blower wheel 63 lies between these two planes. Room or indoor air will be discharged against arcuate portion 38 of air deflecting ring 32 and out outlet opening 42 from the area between the plane of flat air deflecting ring portion 36 and blower wheel partition 66. Outdoor air will be discharged from the blower wheel in the area between partition 66 and the plane of mounting plate 26. Thus, with partition 66 positioned as shown in FIGURE 2, the air discharged through outlet opening 42 will have a fixed, predetermined ratio of room to outdoor air.

The ratio of indoor to outdoor air may be varied by shifting blower wheel partition 66 relative to the plane of deflecting ring flat wall portion 36 and the plane of mounting plate 26. This is accomplished by shifting ring 46 (and, therefore, blower motor 56 and blower wheel 63) longitudinally in room air inlet cylinder 44. The elongated slots 50 in cylinder 44, as discussed above, accommodate this movement. The limits of this movement are indicated in FIGURE 2 by broken line 70 and dot-dash 6 line 72 which represent the extreme positions of the end 67 of blower wheel 63.

As the air discharged through blower outlet opening 42 moves parallel to wall 12 closely adjacent its surface, as the cold outdoor air is warmed by mixing it with recirculated room air, and as the air discharge velocity diminishes as the air travels away from blower 8, drafty conditions will not be created by the blower operation. On the other hand, as the blower housing is designed so that there is very little resistance to the radial flow of the air, the capacity of the blower is very great for its size and the blower is highly effective for diluting and removing combustion products from an enclosed space and for preventing the formation of condensate on the enclosures interior wall surfaces when employed in the manner suggested above.

For some applications it may be desirable to circulate the outdoor air and the room air in separate curtains. For this purpose, air deflecting ring 32 may be replaced with a flat plate. With a flat plate installed, parallel streams of outdoor and room air will be discharged from blower opening 42 with the curtain of warmer recirculated air between the cooler curtain of outdoor air and the interior of the room.

In the modification of blower 8 shown in FIGURES 4 and 5 and identified by reference character 98, elements identical to the corresponding elements of blower 8 are identified by the same reference characters. In this modification dished air deflecting ring 32 is replaced by a conical air deflecting ring 99. The conical ring causes the streams or curtains of outdoor and indoor air to intermingle gradually as they fan out from the blower and their velocity decreases. Air deflecting ring 99 is sup ported from mounting plate 26 by screws 27.

In blower 98, the housing of motor 56 is bolted to a plate 101 by bolts 102. An adjusting screw 103, the axis of which is coincidental with the center line of motor 56, is welded to plate 101 and extends through a nut 104 which is attached to and supported by two arms 106 secured by screws 107 in air inlet cylinder 44. A hand wheel 108 is fixed to the end of adjusting screw 103 opposite plate 101. Rotation of handwheel108 moves screw 103 longitudinally in nut 104, thereby moving motor 56 and blower wheel 63 longitudinally with respect to mounting plate 26 and air deflecting ring 9 9 and varying the ratio of outdoor air to indoor air.

Adusting screw 103 is preferably of suflicient length that end 67 of blower wheel 63 can be moved from the position indicated by broken line 110 in FIGURE 4 to that indicated by dot-dash line 112. With blower wheel end 67 in the position indicated by line 112, all of the air discharged from the blower is drawn into it through inlet sleeve 28 from the exterior of building 10. When blower end 67 is in the position indicated by line 112, all of the air circulated by blower 98 is drawn through inlet cylinder 44 from the interior of the building. As blower end 67 is moved to positions intermediate the extreme positions indicated by lines 110 and 112, mixtures of indoor and outdoor air in varying ratios will be discharged by the blower. Thus, any desired ratio of outdoor air to indoor air can be provided simply by turning the handwheel 108.

When blowers 8 or 98 are used to supply air to a building heated by unvented combustion units, as shown in FIGURE 1, it is usually deemed desirable to operate the blowers only when the heaters are on to prevent the loss of heat which would occur if the blowers brought in cool outdoor air when no heat was being furnished. This mode of blower operation is provided by the controls shown in FIGURE 6.

Three valves 150, 152 and 154 are installed in gas supply pipe 18 ahead of the heaters 16, only one of which is shown in FIGURE '6. Valves and 152 aremanually operated and valve 154 is an electrically operated solenoid or motorized valve and will hereafter-be referred to as a motorized valve. Connected to supply pipe 18 between valves 150 and 152 is a branch pipe 155 which supplies gas to pilot burners 158 of any suitable construction for igniting heaters 16 (only one pilot burner is shown in FIG- URE 6). As long as valve 150 is open, gas will be supplied to the pilot burners which may be ignited by a match or an electric ignitor (not shown). Valve 150 can be closed to turn off gas to both heaters 16 and pilot burners 158, and valve 152 can be closed to turn the heaters on or off without extinguishing the pilot burners.

Operating voltage is applied to leads L1 and L2 when manually-operated main switch 160 is closed. Lead L1 is connected to one terminal of the motor or solenoid (not shown) of motorized valve 154 and to one terminal of each of the blower motors 56 of which two are shown and the number of which may be varied as desired. Lead L2 is connected through a thermostat 162 to the other terminal of the motor or solenoid of valve 154 and each of the blower motors 56. If main switch 160'is closed when the building temperature drops below the setting of thermostat 162, operating voltage will be applied to motorized valve 154 and blower motors 56, opening valve 154 and driving blower wheels 63. If manual valves 150 and 152 are open, gas will be supplied to heaters 16 which will be ignited from pilot burners 158. When the interior building temperature reaches the temperature set on thermostat 162, the circuits to motorized valve 154 and blower motors 56 will be interrupted, shutting off the supply of gas to heaters 16 and discontinuing the circulation of air by the blowers.

Thermostat 162 is illustrated in FIGURE 6 as a directacting bimetal thermostat, but may be of any type and may operate a relay to complete the above-described circuit, instead of being interposed directly in lead L2.

Referring now to FIGURE 7, a blower of the type provided by the present invention can be installed in a ceiling of a room for draftless room ventilation. The building 200 illustrated diagrammatically in FIGURE 7 has side walls 202 and a roof 204. Spaced below roof 294 is the ceiling 206 of a room 208 which provides attic space 210. Air inlets 212 are provided in roof 204 and air outlets or vents 214 are provided in side walls 202. A blower 216, which may be of the type shown in FIGURES 2 and 3 or of the type shown in FIGURES 4 and 5, is installed in a hole 217 in the ceiling 206 with its blower shaft (not shown) vertical and its motor 218 below the ceiling.

When blower 216 is operated, either manually or automatically, fresh outdoor air will be drawn into blower 216 (as shown by the arrows) through air inlet 212 and discharged along the under side of the ceiling. Room air will be drawn into blower 216 from room 208 and will mix with and temper the fresh air. The outdoor air brought into the room will replace stale room air which will be forced out through vents 214. Thus, air laden with smoke, odor, and excess humidity can be removed and replaced with fresh air without creating a drafty condition in the room.

If the building has no attic space, blower 216 can be installed in an appropriate opening in its roof. In this event, the blower inlet extending upward through the roof is preferably surmounted with a cover to prevent entrance of rain or snow.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by Letters Patent is:

1. The method of heating and ventilating a building having vent openings in its upper reaches, comprising steps of:

(a) heating said building substantially solely with unvented gas-fired heaters;

(b) allowing unrestricted escape of the combustion products from said heaters;

(c) providing an outdoor air inlet opening remote from said heaters;

(d) drawing through said inlet opening outdoor air which is substantially free of said combustion products;

(e) distributing said outdoor air prior to mixing with said combustion products as a thin curtain extending from said inlet opening along interior wall surfaces of said building and moving past said heaters to mix with and dilute with said combustion products; and

(f) removing the admixed outdoor air and diluted combustion products from said building through said vent openings.

2. The method as defined in claim 1 including the steps of:

(a) drawing air from the interior of said building; and

(b) mixing said interior air with said outdoor air before distributing the latter.

3. The method as defined in claim 1 including the steps of:

(a) drawing air from the interior of said building; and

(b) distributing said indoor air as a curtain adjacent said curtain of outdoor air.

4. A ventilating apparatus for an enclosed space bounded at least in part by a exterior wall having an inlet air opening therein, said ventilating apparatus comprising:

(a) a blower wheel assembly extending into said enclosed space at least partially forwardly of the interior surface of said wall for radially discharging air approximately parallel to the interior surface of said exterior wall;

(b) a partition extending forwardly of said wall and transversely dividing the interior of said blower wheel assembly into a plurality of compartments;

(c) means for driving said blower wheel;

(d) said blower wheel assembly being so disposed with respect to said inlet opening and said enclosed space as to draw in inside air and outdoor air from opposite ends thereof and to discharge said inside air and said outdoor air on opposite sides of said partition; and

(e) deflecting surface means disposed within said enclosed space forwardly of said exterior wall for deflecting air discharged by said blower wheel assembly at least partially toward said exterior wall.

5. The ventilating apparatus defined in claim 4 including means for selectively axially displacing said partition relative to said blower wheel assembly for varying the ratio of outdoor air to inside air drawn in from opposite ends of said blower wheel assembly.

6. In combination with a building having an exterior top wall provided with a vent opening and at least one side wall provided with an inlet air opening, building heating and ventilating means, comprising:

(a) at least one unvented combustion type radiant heater in the upper part of said building;

(b) an open ended blower wheel;

(c) a partition mounted in said blower wheel and extending transversely to divide the interior of said blower wheel into two chambers;

(d) means for driving said blower wheel;

(c) said blower wheel being disposed within said building adjacent said inlet air opening for drawing in outdoor air through one end thereof and for drawing in air from the interior of said building through the other end thereof;

(f) means for selectively axially displacing said partition for varying the ratio of outdoor air to indoor air respectively drawn in through opposite ends of said blower Wheel; and

(g) means for distributing the air discharged by said blower wheel in the form of a curtain along the side Wall of said building to move past said heater and out said vent opening for diluting combustion products generated by the heater.

7. The combination as defined in claim 6 including control means for starting and stopping said heater and said recirculating and fresh air blower means simultaneously.

8. The combination as defined in claim 7 wherein said control means includes means responsive to the temperature in said building.

9. In a forced draft ventilating blower:

(a) a rotatably mounted open-ended blower wheel having means for drawing air into said wheel through said open ends and discharging it normal to the axis of rotation of said wheel;

(b) means for rotating said blower wheel;

(e) housing means surrounding said blower wheel and including first and second straight, axially aligned cylindrical casings communicating with the opposite ends of said blower wheel; and

(d) means providing a radial discharge opening around the periphery of said housing intermediate the ends of the blower wheel; and

(e) means for guiding the air discharged by said blower wheel through the radial discharge opening in a radially expanding curtain, said guiding means comprising an air deflecting member located between the ends of the blower wheel, oriented substantially normal to said housing, and having a peripheral portion extending at an angle to the housing and terminating in an edge concentric with said housing and defining one side of the radial discharge opensing.

10. The ventilating blower as defined in claim 9 including partition means in said blower wheel between the open ends thereof and means for varying the position of said partition means relative to said peripheral outlet opening.

11. The ventilating blower as defined in claim 10 wherein the means for varying the position of said partition includes:

(a) means in one of said conduit means supporting said blower wheel; and

(b) means fastening said supporting means to said conduit means, said fastening means being selectively releasable to permit movement of said supporting means relative to said conduit means.

12. The ventilating blower as defined in claim 10 wherein said blower wheel is supported by said blower wheel rotating means and said means for varying the position of said partition means includes:

(a) an internally threaded member fixed to one of said conduit means;

(b) a threaded shaft extending through said internally threaded member and operatively engaged therewith; and

(0) means fixing said threaded shaft to said blower wheel rotating means.

13. The ventilating blower as defined in claim 9 wherein the peripheral portion of said air deflecting member has a substantially arcuate cross section and the concave side of said member faces the blower wheel.

14. The ventilating blower as defined in claim 9 wherein said air deflecting member has a fmsto-conical configuration.

References Cited by the Examiner UNITED STATES PATENTS 1,594,074 7/26 Shuell et a1 12684 2,051,213 8/36 Hamilton 126--92 2,217,944 10/40 Collicutt 9838 2,316,098 4/43 Moss et a1 9838 X 2,398,627 4/46 Disbro et a1 98-38 2,611,599 9/52 MacCracken et a1 26319 2,841,381 7/58 Jones 26319 3,020,819 2/62 Kunen 9838 CHARLES SUKALO, Primary Examiner.

JOHN J. CAMBY, PERCY L. PATRICK, Examiners. 

1. THE METHOD OF HEATING AND VENTILATING A BUILDING HAVING VENT OPENINGS IN ITS UPPER REACHES, COMPRISING STEPS OF: (A) HEATING SAID BUILDING SUBSTANTIALLY SOLELY WITH UNVENTED GAS-FIRED HEATERS; (B) ALLOWING UNRESTRICTED ESCAPE OF THE COMBUSTION PRODUCTES FROM SAID HEATERS; (C) PROVIDING AN OUTDOOR AIR INLET OPENING REMOTE FROM SAID HEATERS; (D) DURING THROUGH SAID INLET OPENING OUTDOOR AIR WHICH IS SUBSTANTIALLY FREE OF SAID COMBUSTION PRODUCTS; (E) DISTRIBUTING SAID OUTDOOR AIR PRIOR TO MIXING WITH SAID COMBUSTION PRODUCTS AS A THIN CURTAIN EXTENDING FROM SAID INLET OPENING ALONG INTERIOR WALL SURFACES OF SAID BUILDING AND MOVING PAST SAID HEATERS TO MIX WITH AND DILUTE WITH THE SAID COMBUSTION PRODUCTS; AND (F) REMOVING THE ADMIXED OUTDOOR AIR AND DILUTED COMBUSTION PRODUCTS FROM SAID BUILDIND THROUGH SAID VENT OPENINGS. 